Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 94960 — San Anselmo, CA

ZIP code 94960 (San Anselmo, Marin County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F.

Where ZIP 94960 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone9b25 to 30 °F
Coldest night−3.9 to −1.1 °C
Last frostrare
First frostrare
2012 zone10a

Was 10a on the 2012 map — half a zone colder now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for San Anselmo, CA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station San Rafael Civic Center, CA — 2 miles away, elevation 121 ft) the median growing season is 349 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 94960 came on Jan 29 — about the same time as the 1991–2020 average (Jan 29).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Soil in San Anselmo, CA

The center of ZIP 94960 is mapped as Xerorthents-Urban land complex, 0 to 9 percent slopes: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 94960; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in San Anselmo, CA

Summer high81 °Faverage high, July
Winter low42 °Faverage low, December
Hot days20days a year at 90 °F or more
Freezing nights3nights a year at 32 °F or less
Growing degree days3,652base 50 °F — the season’s usable heat
Longest day14 h 48 mindaylight on June 21
Shortest day9 h 31 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation36.3 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°32 °FJanuary: average high 57 °F, low 43 °F 57°43° JanFebruary: average high 61 °F, low 44 °F 61°44° FebMarch: average high 65 °F, low 46 °F 65°46° MarApril: average high 68 °F, low 48 °F 68°48° AprMay: average high 72 °F, low 51 °F 72°51° MayJune: average high 78 °F, low 54 °F 78°54° JunJuly: average high 81 °F, low 55 °F 81°55° JulAugust: average high 81 °F, low 56 °F 81°56° AugSeptember: average high 81 °F, low 54 °F 81°54° SepOctober: average high 75 °F, low 51 °F 75°51° OctNovember: average high 65 °F, low 46 °F 65°46° NovDecember: average high 57 °F, low 42 °F 57°42° Dec

Precipitation by month inches

0″2″4″6″8″January: 7.59 in precipitation 7.6 JanFebruary: 7.60 in precipitation 7.6 FebMarch: 4.92 in precipitation 4.9 MarApril: 1.95 in precipitation 1.9 AprMay: 0.85 in precipitation 0.8 MayJune: 0.25 in precipitation 0.3 JunJuly: 0.01 in precipitation 0.0 JulAugust: 0.05 in precipitation 0.1 AugSeptember: 0.11 in precipitation 0.1 SepOctober: 1.45 in precipitation 1.4 OctNovember: 3.43 in precipitation 3.4 NovDecember: 8.04 in precipitation 8.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: San Rafael Civic Center, CA (2 mi away); precipitation: San Anselmo 2.0 Nnw, CA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

2 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

All 2 ZIP codes in San Anselmo → · California planting zones →

Questions about 94960

What planting zone is ZIP code 94960?

ZIP code 94960 (San Anselmo, CA) is in USDA hardiness zone 9b on the 2023 map: the coldest night of an average winter reaches 25 to 30 °F (−3.9 to −1.1 °C).

How much rain and snow does 94960 get?

About 36.3 inches of precipitation a year (NOAA 1991–2020 normals, San Anselmo 2.0 Nnw station).

How hot do summers get in San Anselmo, CA?

The average high peaks at 81 °F in July, with about 20 days a year at 90 °F or more.

Did spring come early in San Anselmo, CA in 2026?

Spring leaf-out near 94960 came on Jan 29 in 2026, about the same as the 1991–2020 average (Jan 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in San Anselmo, CA?

Intermediate onions: the longest day near 94960 is 14 h 48 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 94960 change?

Yes. The 2012 USDA map put 94960 in zone 10a; the 2023 map puts it in zone 9b. The newer map uses 1991–2020 data and more weather stations.